avfilter/af_astats: improve options descriptions

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>

doc/filters.texi

@@ -2962,16 +2962,17 @@ this @code{lavfi.astats.Overall.Peak_count}.
 For description what each key means read below.
 
 @item reset
-Set number of frame after which stats are going to be recalculated.
+Set the number of frames over which cumulative stats are calculated before
+being reset
 Default is disabled.
 
 @item measure_perchannel
-Select the entries which need to be measured per channel. The metadata keys can
+Select the parameters which are measured per channel. The metadata keys can
 be used as flags, default is @option{all} which measures everything.
 @option{none} disables all per channel measurement.
 
 @item measure_overall
-Select the entries which need to be measured overall. The metadata keys can
+Select the parameters which are measured overall. The metadata keys can
 be used as flags, default is @option{all} which measures everything.
 @option{none} disables all overall measurement.
 

libavfilter/af_astats.c

@@ -114,8 +114,8 @@ typedef struct AudioStatsContext {
 static const AVOption astats_options[] = {
     { "length", "set the window length", OFFSET(time_constant), AV_OPT_TYPE_DOUBLE, {.dbl=.05}, 0, 10, FLAGS },
     { "metadata", "inject metadata in the filtergraph", OFFSET(metadata), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
-    { "reset", "recalculate stats after this many frames", OFFSET(reset_count), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS },
-    { "measure_perchannel", "only measure_perchannel these per-channel statistics", OFFSET(measure_perchannel), AV_OPT_TYPE_FLAGS, {.i64=MEASURE_ALL}, 0, UINT_MAX, FLAGS, "measure" },
+    { "reset", "Set the number of frames over which cumulative stats are calculated before being reset", OFFSET(reset_count), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS },
+    { "measure_perchannel", "Select the parameters which are measured per channel", OFFSET(measure_perchannel), AV_OPT_TYPE_FLAGS, {.i64=MEASURE_ALL}, 0, UINT_MAX, FLAGS, "measure" },
       { "none"                      , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NONE                }, 0, 0, FLAGS, "measure" },
       { "all"                       , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_ALL                 }, 0, 0, FLAGS, "measure" },
       { "DC_offset"                 , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_DC_OFFSET           }, 0, 0, FLAGS, "measure" },
@@ -143,7 +143,7 @@ static const AVOption astats_options[] = {
       { "Number_of_NaNs"            , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NUMBER_OF_NANS      }, 0, 0, FLAGS, "measure" },
       { "Number_of_Infs"            , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NUMBER_OF_INFS      }, 0, 0, FLAGS, "measure" },
       { "Number_of_denormals"       , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NUMBER_OF_DENORMALS }, 0, 0, FLAGS, "measure" },
-    { "measure_overall", "only measure_perchannel these overall statistics", OFFSET(measure_overall), AV_OPT_TYPE_FLAGS, {.i64=MEASURE_ALL}, 0, UINT_MAX, FLAGS, "measure" },
+    { "measure_overall", "Select the parameters which are measured overall", OFFSET(measure_overall), AV_OPT_TYPE_FLAGS, {.i64=MEASURE_ALL}, 0, UINT_MAX, FLAGS, "measure" },
     { NULL }
 };